If you like wild Chinook doom and gloom with a dash or two of bright spots to keep hope alive, you’ll love what’s being billed as a “comprehensive” synthesis of long-term population data for stocks from Vancouver, BC, down to Sacramento that was released this week.
Broadly speaking, natural-origin springers returning to interior watersheds like the Columbia, Snake and Fraser Rivers, as well as most California stocks, are faring poorly, while summer and fall kings are generally exhibiting a mixed bag of trends, and a select few populations are responding well to fish passage improvements and other restoration work, according to researchers from the Wild Salmon Center, NMFS, WDFW, Canada’s DFO and British Columbia’s Simon Fraser University.
They also call for maintaining the diversity of native Chinook runs in the face of climate change, marine heat waves, pinniped predation, massive pink salmon production in the North Pacific and all the other challenges the salmon face, as well as narrowing fisheries from mixed stock to more selective terminal ones.
Their paper was published Tuesday in the journal Fish and Fisheries. It’s essentially nothing we don’t already know or haven’t been advised about before, nor does it vary from the take-home message of Washington’s latestSalmon in Watersheds report: most Evergreen State salmon stocks are declining but a few are showing optimistic signs, so keep plugging away, tiger.
All of which is not to rain too heavily on the authors’ 23-page paper entitled “Trends in Chinook salmon spawner abundance and total run size highlight linkages between life history, geography and decline.”
They looked at as much as 30 years of spawning abundance information from 79 different native runs and harvest information through 2019, then crunched the numbers to determine average number of spawners and how that compares with five- and 15-year means, and whether trends are positive or negative.
Seventy percent are seeing declining abundance, but even as some spring Chinook stocks are having a hard go of it – particularly in Idaho and salmon-water-profligate California – others much closer to the Pacific “stand out,” in the authors’ words, and offer encouragement to do more.
They point to Oregon’s Clackamas and Sandy fish, which they say have “benefitted directly from ecosystem restoration or dam removal” and other fixes, performed by Portland General Electric and related to federal dam relicensing requirements. Upgraded fish passage for outmigrating smolts and returning adults on the Clack have helped the population rebuild itself, with runs from 2015-19 “exceeding the long-term average by 103 percent.” With 2007’s removal of Marmot Dam, escapement on the Sandy over the past five years has been 144 percent higher than it averaged from 1982-2019.
As for boosting returns of those Inland Northwest springers, the authors’ words won’t earn them any friends among the region’s Congressional delegation, who have introduced legislation to protect dams, but will add to a steady drumbeat from salmon advocates and some politicians.
“Dam removal on the Snake River is among the clearest pathways to recovery for Chinook in the Columbia Basin, and recent analyses indicate that unless survival rates are improved for out-migrating Chinook smolts and returning adults extinction is likely for many of these stocks before the end of the 21st century. Removing dams from migratory corridors may also boost marine survival of out-migrating smolts, since carryover effects from migration through the hydro system including reduced condition or energy storage at ocean entry have been linked to lower smolt-to-adult returns,” they write.
The authors state the upcoming removal of four dams on the Klamath holds “immense promise” for the Oregon-California river’s Chinook, but given low springer numbers, “urgent action” may be needed – a way to say hatchery, albeit conservation hatchery, without saying hatchery? No mention is made of removals on the Elwha, where Chinook smolt survival is up but hasn’t produced big jumps in adult returns, but that may also be a data availability limitation issue.
Even as Chinook managers have reduced harvest in response to salmon declines, some populations with shrinking abundances “continue to be harvested at high rates in mixed-stock fisheries,” such as Washington’s Skagit summers and Queets falls at rates greater than 50 and 60 percent, the authors say. Some of that occurs in waters state and tribal managers control, but coded-wire tagging shows 70 percent of harvest happens outside their jurisdictions, “limiting the efficacy of local recovery actions by state and tribal management agencies and reducing access to salmon fishing opportunities for communities in these watersheds,” they write.
And it continues; one wag pointed out how the Pacific Fisheries Management Council this year increased commercial ocean harvest compared to last, shorting in-river fisheries.
The woes of a terminal fishery that’s front and center right now is how a relatively low wild Snohomish River basin Chinook forecast, WDFW and the tribes’ new 10-year management plan and a larger predicted Canadian catch will constrain the system’s inriver hatchery summer king fishery this season, as well as steelhead, pink and coho too. Snohomish Chinook were not part of the study published in Fish and Fisheries.
On the bright side, populations of wild Columbia fall Chinook have “exhibited increasing abundance over the last 30 years” and support “major harvest.” That’s a reference in part to the bounceback of Snake River fish, which while still constraining fisheries, are the result of Nez Perce Tribe restorations.
All in all, the authors say declining U.S. West Coast and Fraser natural-origin king escapement trends “appear to be responding to the combined drivers of management and shifting environmental conditions.” It includes deteriorating river and ocean conditions, such as marine heat waves like The Blob, which heavily impacted the Pacific and Pacific Northwest, higher salmon-eating pinniped populations, massive pink salmon production peaking at half a billion fish likely competing for forage with Chinook, and certain hatchery practices’ effects on Oncy. T. resiliency.
It’s maddening that one wild Chinook stock can be doing well while others of the exact same species elsewhere struggle, but also evidence of how plastic they all are. In a Wild Salmon Center press release meant to amplify the report’s findings, coauthor Dr. Matt Sloat said it “strongly supports the case for maintaining a diverse portfolio of wild Chinook runs across the region.”
“As environmental conditions get tougher, it’s increasingly important that we understand and maintain the different survival strategies that Chinook have honed over millions of years,” Sloat stated.
Liz Hamilton of the pro-fish, -fishing and -dam-removal Northwest Sportfishing Industry Association has worked with WSC in the past on certain matters but was not involved in the paper. She agreed with how critical genetic diversity is for Chinook survival.
“It’s not just the diversity of the genes; it’s how they are triggered – expressed – under changing and dynamic river conditions,” she said. “It is the magic of these fish that it has been the interaction of the genes and the environment that has protected their survival. The less genetic diversity, the less capable a species is to respond to drought, flood, temperatures, ocean conditions, etc. I know we are living with climate change and extreme variability in weather patterns, but salmon have survived for millennia, and may still if we preserve and protect river temperatures, habitat suitable for them and genetic diversity.”
That’s essentially a big 10-4 to the question asked in the headline of the Wild Salmon Center’s press release: “Are Cold Water and Diverse Strategies the Key to Chinook Success?”
Enough people on the same page and we might get somewhere, and you have to have some measure of hope based on hard data.